config metadata agent's nova metadata protocol

If nova all endpoints are over https, the metadata request from metadata agent have to use https. But the configuration are not part of puppet yet.

change to fix

 # The default, count of machine's processors, runs the worker thread in the
@@ -83,6 +86,7 @@ class neutron::agents::metadata (
   $auth_region = 'RegionOne',
   $metadata_ip = '127.0.0.1',
   $metadata_port = '8775',
+ $metadata_protocol = 'http',
   $metadata_workers = $::processorcount,
   $metadata_backlog = '4096',
   $metadata_memory_cache_ttl = 5,
@@ -104,6 +108,7 @@ class neutron::agents::metadata (
     'DEFAULT/admin_password': value => $auth_password, secret => true;
     'DEFAULT/nova_metadata_ip': value => $metadata_ip;
     'DEFAULT/nova_metadata_port': value => $metadata_port;
+ 'DEFAULT/nova_metadata_protocol': value => $metadata_protocol;
     'DEFAULT/metadata_proxy_shared_secret': value => $shared_secret;
     'DEFAULT/metadata_workers': value => $metadata_workers;
     'DEFAULT/metadata_backlog': value => $metadata_backlog;